<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>chsolve</title>
  </head>
  <body bgcolor="#FFFFFF">
    <center>Scilab Function</center>
    <div align="right">Last update : 28/06/2006</div>
    <p>
      <b>chsolve</b> -  sparse Cholesky solver</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>sol=chsolve(spcho,rhs)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>spcho</b>
        </tt>: list containing the Cholesky factors in coded form returned by chfact</li>
      <li>
        <tt>
          <b>rhs, sol</b>
        </tt>: full column vectors</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>sol=chsolve(spcho,rhs)</b>
      </tt> computes the solution of 
      <tt>
        <b>rhs=A*sol</b>
      </tt>, with <tt>
        <b>A</b>
      </tt> a symmetric sparse positive definite
      matrix. This function is based on the Ng-Peyton programs (ORNL). See the
      Fortran programs for a complete description of the variables in
      <tt>
        <b>spcho</b>
      </tt>.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>
    
    A=sprand(20,20,0.1);
    A=A*A'+eye();  
    spcho=chfact(A);
    sol=(1:20)';rhs=A*sol;
    spcho=chfact(A);
    chsolve(spcho,rhs)
    
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="chfact.htm">
        <tt>
          <b>chfact</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../elementary/sparse.htm">
        <tt>
          <b>sparse</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="lufact.htm">
        <tt>
          <b>lufact</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="luget.htm">
        <tt>
          <b>luget</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="spchol.htm">
        <tt>
          <b>spchol</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
  </body>
</html>
